//
//  KBAICommentView.m
//  keyBoard
//
//  Created by Mac on 2026/1/16.
//

#import "KBAICommentView.h"
#import "KBAICommentFooterView.h"
#import "KBAICommentHeaderView.h"
#import "KBAICommentInputView.h"
#import "KBAICommentModel.h"
#import "KBAIReplyCell.h"
#import "KBAIReplyModel.h"
#import <MJExtension/MJExtension.h>
#import <Masonry/Masonry.h>

static NSString *const kCommentHeaderIdentifier = @"CommentHeader";
static NSString *const kReplyCellIdentifier = @"ReplyCell";
static NSString *const kCommentFooterIdentifier = @"CommentFooter";

/// 每次展开的回复数量
static NSInteger const kRepliesLoadCount = 3;

@interface KBAICommentView () <UITableViewDataSource, UITableViewDelegate>

@property(nonatomic, strong) UIView *headerView;
@property(nonatomic, strong) UILabel *titleLabel;
@property(nonatomic, strong) UIButton *closeButton;
@property(nonatomic, strong) UITableView *tableView;
@property(nonatomic, strong) KBAICommentInputView *inputView;

@property(nonatomic, strong) NSMutableArray<KBAICommentModel *> *comments;
@property(nonatomic, assign) NSInteger totalCommentCount;

/// 键盘高度
@property(nonatomic, assign) CGFloat keyboardHeight;
/// 输入框底部约束
@property(nonatomic, strong) MASConstraint *inputBottomConstraint;

@end

@implementation KBAICommentView

#pragma mark - Lifecycle

- (instancetype)initWithFrame:(CGRect)frame {
  self = [super initWithFrame:frame];
  if (self) {
    self.comments = [NSMutableArray array];
    [self setupUI];
    [self setupKeyboardObservers];
    [self loadComments];
  }
  return self;
}

- (void)dealloc {
  [[NSNotificationCenter defaultCenter] removeObserver:self];
}

#pragma mark - UI Setup

- (void)setupUI {
  self.backgroundColor = [UIColor whiteColor];
  self.layer.cornerRadius = 12;
  self.layer.maskedCorners = kCALayerMinXMinYCorner | kCALayerMaxXMinYCorner;
  self.clipsToBounds = YES;

  [self addSubview:self.headerView];
  [self.headerView addSubview:self.titleLabel];
  [self.headerView addSubview:self.closeButton];
  [self addSubview:self.tableView];
  [self addSubview:self.inputView];

  [self.headerView mas_makeConstraints:^(MASConstraintMaker *make) {
    make.top.left.right.equalTo(self);
    make.height.mas_equalTo(50);
  }];

  [self.titleLabel mas_makeConstraints:^(MASConstraintMaker *make) {
    make.center.equalTo(self.headerView);
  }];

  [self.closeButton mas_makeConstraints:^(MASConstraintMaker *make) {
    make.right.equalTo(self.headerView).offset(-16);
    make.centerY.equalTo(self.headerView);
    make.width.height.mas_equalTo(30);
  }];

  [self.inputView mas_makeConstraints:^(MASConstraintMaker *make) {
    make.left.right.equalTo(self);
    make.height.mas_equalTo(50);
    self.inputBottomConstraint = make.bottom.equalTo(self);
  }];

  [self.tableView mas_makeConstraints:^(MASConstraintMaker *make) {
    make.top.equalTo(self.headerView.mas_bottom);
    make.left.right.equalTo(self);
    make.bottom.equalTo(self.inputView.mas_top);
  }];
}

#pragma mark - Keyboard Observers

- (void)setupKeyboardObservers {
  [[NSNotificationCenter defaultCenter]
      addObserver:self
         selector:@selector(keyboardWillShow:)
             name:UIKeyboardWillShowNotification
           object:nil];
  [[NSNotificationCenter defaultCenter]
      addObserver:self
         selector:@selector(keyboardWillHide:)
             name:UIKeyboardWillHideNotification
           object:nil];
}

- (void)keyboardWillShow:(NSNotification *)notification {
  CGRect keyboardFrame =
      [notification.userInfo[UIKeyboardFrameEndUserInfoKey] CGRectValue];
  NSTimeInterval duration =
      [notification.userInfo[UIKeyboardAnimationDurationUserInfoKey]
          doubleValue];

  self.keyboardHeight = keyboardFrame.size.height;

  [self.inputBottomConstraint uninstall];
  [self.inputView mas_updateConstraints:^(MASConstraintMaker *make) {
    self.inputBottomConstraint =
        make.bottom.equalTo(self).offset(-self.keyboardHeight);
  }];

  [UIView animateWithDuration:duration
                   animations:^{
                     [self layoutIfNeeded];
                   }];
}

- (void)keyboardWillHide:(NSNotification *)notification {
  NSTimeInterval duration =
      [notification.userInfo[UIKeyboardAnimationDurationUserInfoKey]
          doubleValue];

  self.keyboardHeight = 0;

  [self.inputBottomConstraint uninstall];
  [self.inputView mas_updateConstraints:^(MASConstraintMaker *make) {
    self.inputBottomConstraint = make.bottom.equalTo(self);
  }];

  [UIView animateWithDuration:duration
                   animations:^{
                     [self layoutIfNeeded];
                   }];
}

#pragma mark - Data Loading

- (void)loadComments {
  NSString *filePath = [[NSBundle mainBundle] pathForResource:@"comments_mock"
                                                       ofType:@"json"];
  if (!filePath) {
    NSLog(@"[KBAICommentView] comments_mock.json not found");
    return;
  }

  NSData *data = [NSData dataWithContentsOfFile:filePath];
  if (!data) {
    NSLog(@"[KBAICommentView] Failed to read comments_mock.json");
    return;
  }

  NSError *error;
  NSDictionary *json = [NSJSONSerialization JSONObjectWithData:data
                                                       options:0
                                                         error:&error];
  if (error) {
    NSLog(@"[KBAICommentView] JSON parse error: %@", error);
    return;
  }

  self.totalCommentCount = [json[@"totalCount"] integerValue];
  NSArray *commentsArray = json[@"comments"];

  [self.comments removeAllObjects];
  for (NSDictionary *dict in commentsArray) {
    KBAICommentModel *comment = [KBAICommentModel mj_objectWithKeyValues:dict];
    [self.comments addObject:comment];
  }

  [self updateTitle];
  [self.tableView reloadData];
}

- (void)updateTitle {
  NSString *countText;
  if (self.totalCommentCount >= 10000) {
    countText = [NSString
        stringWithFormat:@"%.1fw条评论", self.totalCommentCount / 10000.0];
  } else {
    countText =
        [NSString stringWithFormat:@"%ld条评论", (long)self.totalCommentCount];
  }
  self.titleLabel.text = countText;
}

#pragma mark - UITableViewDataSource

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
  return self.comments.count;
}

- (NSInteger)tableView:(UITableView *)tableView
    numberOfRowsInSection:(NSInteger)section {
  KBAICommentModel *comment = self.comments[section];
  return comment.displayedReplies.count;
}

- (UITableViewCell *)tableView:(UITableView *)tableView
         cellForRowAtIndexPath:(NSIndexPath *)indexPath {
  KBAIReplyCell *cell =
      [tableView dequeueReusableCellWithIdentifier:kReplyCellIdentifier
                                      forIndexPath:indexPath];

  KBAICommentModel *comment = self.comments[indexPath.section];
  KBAIReplyModel *reply = comment.displayedReplies[indexPath.row];
  [cell configureWithReply:reply];

  __weak typeof(self) weakSelf = self;
  cell.onLikeAction = ^{
    // TODO: 处理点赞逻辑
    reply.isLiked = !reply.isLiked;
    reply.likeCount += reply.isLiked ? 1 : -1;
    [weakSelf.tableView reloadRowsAtIndexPaths:@[ indexPath ]
                              withRowAnimation:UITableViewRowAnimationNone];
  };

  return cell;
}

#pragma mark - UITableViewDelegate

- (UIView *)tableView:(UITableView *)tableView
    viewForHeaderInSection:(NSInteger)section {
  KBAICommentHeaderView *header = [tableView
      dequeueReusableHeaderFooterViewWithIdentifier:kCommentHeaderIdentifier];

  KBAICommentModel *comment = self.comments[section];
  [header configureWithComment:comment];

  __weak typeof(self) weakSelf = self;
  header.onLikeAction = ^{
    // TODO: 处理点赞逻辑
    comment.isLiked = !comment.isLiked;
    comment.likeCount += comment.isLiked ? 1 : -1;
    [weakSelf.tableView reloadSections:[NSIndexSet indexSetWithIndex:section]
                      withRowAnimation:UITableViewRowAnimationNone];
  };

  return header;
}

- (UIView *)tableView:(UITableView *)tableView
    viewForFooterInSection:(NSInteger)section {
  KBAICommentModel *comment = self.comments[section];
  KBAIReplyFooterState state = [comment footerState];

  // 无二级评论时返回空视图
  if (state == KBAIReplyFooterStateHidden) {
    NSLog(@"[KBAICommentView] footer hidden section=%ld", (long)section);
    return nil;
  }

  KBAICommentFooterView *footer = [tableView
      dequeueReusableHeaderFooterViewWithIdentifier:kCommentFooterIdentifier];
  [footer configureWithComment:comment];

  __weak typeof(self) weakSelf = self;
  footer.onAction = ^{
    [weakSelf handleFooterActionForSection:section];
  };

  return footer;
}

- (CGFloat)tableView:(UITableView *)tableView
    heightForHeaderInSection:(NSInteger)section {
  return UITableViewAutomaticDimension;
}

- (CGFloat)tableView:(UITableView *)tableView
    heightForFooterInSection:(NSInteger)section {
  KBAICommentModel *comment = self.comments[section];
  KBAIReplyFooterState state = [comment footerState];

  if (state == KBAIReplyFooterStateHidden) {
    return CGFLOAT_MIN;
  }
  return 30;
}

- (CGFloat)tableView:(UITableView *)tableView
    estimatedHeightForHeaderInSection:(NSInteger)section {
  return 100;
}

- (CGFloat)tableView:(UITableView *)tableView
    estimatedHeightForRowAtIndexPath:(NSIndexPath *)indexPath {
  return 60;
}

#pragma mark - Footer Actions

- (void)handleFooterActionForSection:(NSInteger)section {
  KBAICommentModel *comment = self.comments[section];
  KBAIReplyFooterState state = [comment footerState];

  switch (state) {
  case KBAIReplyFooterStateExpand:
  case KBAIReplyFooterStateLoadMore: {
    [self loadMoreRepliesForSection:section];
    break;
  }
  case KBAIReplyFooterStateCollapse: {
    [self collapseRepliesForSection:section];
    break;
  }
  default:
    break;
  }
}

- (void)loadMoreRepliesForSection:(NSInteger)section {
  KBAICommentModel *comment = self.comments[section];
  NSInteger currentCount = comment.displayedReplies.count;
  NSDictionary *anchor = [self captureHeaderAnchorForSection:section];

  NSLog(@"[KBAICommentView] loadMore(before) section=%ld offsetY=%.2f contentSizeH=%.2f boundsH=%.2f rows=%ld",
        (long)section,
        self.tableView.contentOffset.y,
        self.tableView.contentSize.height,
        self.tableView.bounds.size.height,
        (long)currentCount);

  // 加载更多
  [comment loadMoreReplies:kRepliesLoadCount];

  // 计算新增的行
  NSInteger newCount = comment.displayedReplies.count;
  NSMutableArray *insertIndexPaths = [NSMutableArray array];
  for (NSInteger i = currentCount; i < newCount; i++) {
    [insertIndexPaths addObject:[NSIndexPath indexPathForRow:i
                                                   inSection:section]];
  }

  // 更新（避免动画导致跳动）
  [UIView performWithoutAnimation:^{
    [self.tableView beginUpdates];
    if (insertIndexPaths.count > 0) {
      [self.tableView insertRowsAtIndexPaths:insertIndexPaths
                            withRowAnimation:UITableViewRowAnimationNone];
    }
    [self.tableView endUpdates];
    [self.tableView layoutIfNeeded];
    [self restoreHeaderAnchor:anchor];
  }];

  NSLog(@"[KBAICommentView] loadMore(after) section=%ld offsetY=%.2f contentSizeH=%.2f boundsH=%.2f rows=%ld",
        (long)section,
        self.tableView.contentOffset.y,
        self.tableView.contentSize.height,
        self.tableView.bounds.size.height,
        (long)comment.displayedReplies.count);
  dispatch_async(dispatch_get_main_queue(), ^{
    NSLog(@"[KBAICommentView] loadMore(next) section=%ld offsetY=%.2f contentSizeH=%.2f boundsH=%.2f viewBoundsH=%.2f",
          (long)section,
          self.tableView.contentOffset.y,
          self.tableView.contentSize.height,
          self.tableView.bounds.size.height,
          self.bounds.size.height);
  });

  // 手动刷新 Footer（避免使用 reloadSections 导致滚动）
  KBAICommentFooterView *footerView =
      (KBAICommentFooterView *)[self.tableView footerViewForSection:section];
  if (footerView) {
    [footerView configureWithComment:comment];
  }
}

- (void)collapseRepliesForSection:(NSInteger)section {
  KBAICommentModel *comment = self.comments[section];
  NSInteger rowCount = comment.displayedReplies.count;
  NSDictionary *anchor = [self captureHeaderAnchorForSection:section];

  NSLog(@"[KBAICommentView] collapse(before) section=%ld offsetY=%.2f contentSizeH=%.2f boundsH=%.2f rows=%ld",
        (long)section,
        self.tableView.contentOffset.y,
        self.tableView.contentSize.height,
        self.tableView.bounds.size.height,
        (long)rowCount);

  // 计算要删除的行
  NSMutableArray *deleteIndexPaths = [NSMutableArray array];
  for (NSInteger i = 0; i < rowCount; i++) {
    [deleteIndexPaths addObject:[NSIndexPath indexPathForRow:i
                                                   inSection:section]];
  }

  // 收起回复
  [comment collapseReplies];

  // 删除行（避免动画导致跳动）
  [UIView performWithoutAnimation:^{
    [self.tableView beginUpdates];
    if (deleteIndexPaths.count > 0) {
      [self.tableView deleteRowsAtIndexPaths:deleteIndexPaths
                            withRowAnimation:UITableViewRowAnimationNone];
    }
    [self.tableView endUpdates];
    [self.tableView layoutIfNeeded];
    [self restoreHeaderAnchor:anchor];
  }];

  NSLog(@"[KBAICommentView] collapse(after) section=%ld offsetY=%.2f contentSizeH=%.2f boundsH=%.2f rows=%ld",
        (long)section,
        self.tableView.contentOffset.y,
        self.tableView.contentSize.height,
        self.tableView.bounds.size.height,
        (long)comment.displayedReplies.count);
  dispatch_async(dispatch_get_main_queue(), ^{
    NSLog(@"[KBAICommentView] collapse(next) section=%ld offsetY=%.2f contentSizeH=%.2f boundsH=%.2f viewBoundsH=%.2f",
          (long)section,
          self.tableView.contentOffset.y,
          self.tableView.contentSize.height,
          self.tableView.bounds.size.height,
          self.bounds.size.height);
  });

  // 手动刷新 Footer（避免使用 reloadSections 导致滚动）
  KBAICommentFooterView *footerView =
      (KBAICommentFooterView *)[self.tableView footerViewForSection:section];
  if (footerView) {
    [footerView configureWithComment:comment];
  }
}

#pragma mark - Actions

- (void)closeButtonTapped {
  // 关闭评论视图（由外部处理）
  [[NSNotificationCenter defaultCenter]
      postNotificationName:@"KBAICommentViewCloseNotification"
                    object:nil];
}

#pragma mark - Lazy Loading

- (UIView *)headerView {
  if (!_headerView) {
    _headerView = [[UIView alloc] init];
    _headerView.backgroundColor = [UIColor whiteColor];
  }
  return _headerView;
}

- (UILabel *)titleLabel {
  if (!_titleLabel) {
    _titleLabel = [[UILabel alloc] init];
    _titleLabel.font = [UIFont systemFontOfSize:15 weight:UIFontWeightMedium];
    _titleLabel.textColor = [UIColor labelColor];
    _titleLabel.text = @"0条评论";
  }
  return _titleLabel;
}

- (UIButton *)closeButton {
  if (!_closeButton) {
    _closeButton = [UIButton buttonWithType:UIButtonTypeCustom];
    [_closeButton setImage:[UIImage systemImageNamed:@"xmark"]
                  forState:UIControlStateNormal];
    _closeButton.tintColor = [UIColor labelColor];
    [_closeButton addTarget:self
                     action:@selector(closeButtonTapped)
           forControlEvents:UIControlEventTouchUpInside];
  }
  return _closeButton;
}

- (UITableView *)tableView {
  if (!_tableView) {
    _tableView = [[UITableView alloc] initWithFrame:CGRectZero
                                              style:UITableViewStyleGrouped];
    _tableView.dataSource = self;
    _tableView.delegate = self;
    _tableView.backgroundColor = [UIColor whiteColor];
    _tableView.separatorStyle = UITableViewCellSeparatorStyleNone;
    _tableView.estimatedRowHeight = 0;
    _tableView.rowHeight = UITableViewAutomaticDimension;
    _tableView.estimatedSectionHeaderHeight = 0;
    _tableView.estimatedSectionFooterHeight = 0;
    _tableView.sectionHeaderHeight = UITableViewAutomaticDimension;
    _tableView.sectionFooterHeight = UITableViewAutomaticDimension;
    _tableView.keyboardDismissMode = UIScrollViewKeyboardDismissModeOnDrag;

    // 注册 Header/Cell/Footer
    [_tableView registerClass:[KBAICommentHeaderView class]
        forHeaderFooterViewReuseIdentifier:kCommentHeaderIdentifier];
    [_tableView registerClass:[KBAIReplyCell class]
        forCellReuseIdentifier:kReplyCellIdentifier];
    [_tableView registerClass:[KBAICommentFooterView class]
        forHeaderFooterViewReuseIdentifier:kCommentFooterIdentifier];

    // 去掉顶部间距
    if (@available(iOS 15.0, *)) {
      _tableView.sectionHeaderTopPadding = 0;
    }
  }
  return _tableView;
}

- (KBAICommentInputView *)inputView {
  if (!_inputView) {
    _inputView = [[KBAICommentInputView alloc] init];
    _inputView.placeholder = @"说点什么...";

    __weak typeof(self) weakSelf = self;
    _inputView.onSend = ^(NSString *text) {
      // TODO: 发送评论
      NSLog(@"[KBAICommentView] Send comment: %@", text);
      [weakSelf.inputView clearText];
    };
  }
  return _inputView;
}

#pragma mark - Header Anchor

- (NSDictionary *)captureHeaderAnchorForSection:(NSInteger)section {
  CGRect rect = [self.tableView rectForHeaderInSection:section];
  NSLog(@"[KBAICommentView] anchor capture(header) section=%ld rect=%@ offsetY=%.2f contentSizeH=%.2f boundsH=%.2f",
        (long)section,
        NSStringFromCGRect(rect),
        self.tableView.contentOffset.y,
        self.tableView.contentSize.height,
        self.tableView.bounds.size.height);
  if (CGRectIsEmpty(rect) || CGRectIsNull(rect)) {
    NSLog(@"[KBAICommentView] anchor capture(header) empty section=%ld",
          (long)section);
    return nil;
  }

  CGFloat offset = self.tableView.contentOffset.y - rect.origin.y;
  return @{
    @"section" : @(section),
    @"offset" : @(offset),
    @"fallbackOffset" : @(self.tableView.contentOffset.y)
  };
}

- (void)restoreHeaderAnchor:(NSDictionary *)anchor {
  if (!anchor) {
    NSLog(@"[KBAICommentView] anchor restore(header) skipped (nil)");
    return;
  }

  NSInteger section = [anchor[@"section"] integerValue];
  if (section < 0 || section >= self.comments.count) {
    NSLog(@"[KBAICommentView] anchor restore(header) invalid section=%ld",
          (long)section);
    return;
  }

  CGRect rect = [self.tableView rectForHeaderInSection:section];
  NSLog(@"[KBAICommentView] anchor restore(header) section=%ld rect=%@",
        (long)section,
        NSStringFromCGRect(rect));
  if (CGRectIsEmpty(rect) || CGRectIsNull(rect)) {
    NSNumber *fallbackOffset = anchor[@"fallbackOffset"];
    if (!fallbackOffset) {
      NSLog(@"[KBAICommentView] anchor restore(header) no fallback section=%ld",
            (long)section);
      return;
    }
    NSLog(@"[KBAICommentView] anchor restore(header) fallback section=%ld offsetY=%.2f",
          (long)section,
          [fallbackOffset doubleValue]);
    [self setTableViewOffset:[fallbackOffset doubleValue]];
    return;
  }

  CGFloat targetOffsetY = rect.origin.y + [anchor[@"offset"] doubleValue];
  NSLog(@"[KBAICommentView] anchor restore(header) target section=%ld targetY=%.2f",
        (long)section,
        targetOffsetY);
  [self setTableViewOffset:targetOffsetY];
}

- (void)setTableViewOffset:(CGFloat)offsetY {
  UIEdgeInsets inset = self.tableView.adjustedContentInset;
  CGFloat minOffsetY = -inset.top;
  CGFloat maxOffsetY =
      MAX(minOffsetY, self.tableView.contentSize.height + inset.bottom -
                           self.tableView.bounds.size.height);
  CGFloat targetOffsetY = MIN(MAX(offsetY, minOffsetY), maxOffsetY);
  NSLog(@"[KBAICommentView] set offset target=%.2f min=%.2f max=%.2f",
        targetOffsetY,
        minOffsetY,
        maxOffsetY);
  [self.tableView setContentOffset:CGPointMake(0, targetOffsetY)
                          animated:NO];
}

@end